anyone have a t-56 and 4l60e handy?

[dyrt]

Howdy folks,
About a year ago now i started my t-56 swap on my regal and finished sometime in april or so. I originally had a 4l60e in my car. I have a vibe in the car at around 72-80 in sixth and would like to rule out trans angle as a culprit. I checked my driveline angle before and it all seemed ok but i want to rule it out once and for all by making sure everything is mounted as it would be in the factory. Can anyone tell me the height from the center of the output shaft to the mounting surface for the rear mount on the trans for both the t-56 and the 4l60e? I don't have easy access to either right now without taking everything apart, but would like to do some math to check the flange height on my modded crossmember. Thanks for any help! By the way, i know i could but a new crossmember. i am trying to do this low cost and no one seems to want to tell me the perpendicular height from where the CM bolts to the car frame to the mounting surface on the flange. thanks.

Mike

 

[388bu]

Why not buy a cheap angle finder from Sears and measure it that way? Thats what I did back in the day.

Driveshaft balanced by a competent shop? New u-joints? The lower the gear in the rear end the faster the driveshaft will be turning. A 3.42 gear will be less likely to show a driveshaft issue versus a 4.10 gear.

I had a similar issue when I first made the swap. My "brand new" shaft from a local shop was junk. Found a new shop and had him make me a smaller shaft and no troubles since.

 

[dyrt]

i actually did try an angle finder. That is how i got it where it is. The problem was i was doing the swap on my back so i didn't get to lay out some nice reference points to locate the tailshaft of the 6speed when i was doing the swap. I did swap to a 3.73 gear from a 3.42 so that could be it. also, i did get a brand new 3 inch aluminum driveshaft made with 1350 ujoints from shaftmasters. In the end, it could just be a bad exhaust drone mixed with other chassis vibrations. However, i would really like to try to locate the tailshaft where it would be had the whole setup been stock. I could always dig the 4l60e back out and take the measurement, i suppose i only really need the 6-speed measurement. Just trying to figure it out without taking it all back apart is all.


Mike

 

[t5montecarlo]

You mentioned the vibration in 6th gear. Try 5th gear or 4th gear would be even better because you will not be driving the cluster or the OD gears. If the vibration is gone, you can rule out driveshaft angle because the driveshaft speed will not have changed.

 

[dyrt]

You mentioned the vibration in 6th gear. Try 5th gear or 4th gear would be even better because you will not be driving the cluster or the OD gears. If the vibration is gone, you can rule out driveshaft angle because the driveshaft speed will not have changed.

Nah, that's way too obvious. Haha yeah i can't believe i didn't think of that, thanks for the tip! If my mind serves me right i don't think it vibrated as bad in 5th. I'll have to try an 80 mile an hour run in 4th and see how that fares. Are these transmission known to have a smoothness problem when running in overdrive? This trans was probably beat pretty good at some point before i got it so who knows. I just had it apart and nothing seemed wrong but maybe some shimming or whatnot would help out.

Mike